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Turnstones spur a biologist’s wondering By Stewart Janes May 21, 2021 01:00 AM A A The tide at The Capes in Port Orford was receding on a sunny day. From my vantage point high above the ocean I could look down upon the rocks now beginning to reveal the barnacles, mussels, sea palms and other assorted intertidal life. A pelagic cormorant dove for fish in the turbulent water near the rocks at the base of the cliff. A pair of black oystercatchers called. It was then a wave a little higher than most splashed against the rocks, flushing a small flock of birds previously unseen. They flew across a small channel and resumed feeding. The black and white pattern on the back was striking as they flew. I recognized these as black turnstones, a small shorebird common along the rocky shores of the Oregon Coast. There was another bird among them. This one had a white head and a red back. If I had been closer, I could have seen the bold pattern on the side of the neck. It had been many years since I had seen a ruddy turnstone in breeding plumage along the Oregon Coast. Ruddy turnstones breed in coastal tundra around the world from Canada to Siberia. They travel incredible distances in migration to places like the Galapagos Islands, Australia and Argentina. Black turnstones are not so adventurous and are found only from western Alaska to Baja California. Ruddy turnstones, while widespread, are uncommon in Oregon. The name “turnstone” may seem odd, but it is apt. Ruddy turnstones, in particular, frequently feed by flipping small stones and other debris along the shore to reveal a variety of food items. Anyone who has picked up a piece of kelp off the beach has seen the abundance of sand fleas and other life uncovered. Black turnstones prefer rocky areas to sandy beaches and frequently flip the various seaweeds clinging to the rocks hoping to find food. The short, stout bill of both is well-suited to the task. Another shorebird has a different strategy for finding small organisms beneath rocks. The wrybill is a small plover unique to New Zealand, and it has an unusual bill. The bill starts out straight, just as in any other bird, but then it bends sharply about 20 degrees to the right. Hence the name “wrybill.” The bill is used to probe beneath stones (but only from the left) to find hidden prey. The bill is remarkable for its asymmetry. Nature “prefers” symmetry. Scientists have found that among deer, does prefer bucks with symmetrical antlers. As an embryo develops, the process proceeds in an orderly and symmetrical fashion. Asymmetry is the exception. Sedentary organisms such as daisies and sea stars tend to display radial symmetry. Mobile organisms tend to display bilateral symmetry where one side is a mirror image of the other. Humans are bilaterally symmetrical except for the appendix on the right side of the body and the heart, which is more to the left. The genetics that allow a bill to develop with a bend to the right (and it’s always to the right) is beyond my understanding. Even among crossbills, there are some individuals with left crossed bills and some right. I may have to return to the beach to consider this further. Stewart Janes is a retired biology professor at Southern Oregon University. He can be reached at [email protected].